From 42f4393a72c808c6858b29a2343884f12c187e19 Mon Sep 17 00:00:00 2001 From: Di-an Jan Date: Sun, 7 Dec 2008 21:54:45 -0800 Subject: [PATCH] Implement the FIXME that ends an user action with a semicolon if it seems necessary. * src/scan-code.l (flex rules section): Flag cpp directive from any `#' to the first unescaped end-of-line. Semicolon is not needed after `;', `{', '}', or cpp directives and is needed after any other token (whitespaces and comments have no effect). * tests/actions.at (Fix user actions without a trailing semicolon): New test. * tests/input.at (AT_CHECK_UNUSED_VALUES): Add semicolons to to make user actions complete statements. Adjust column numbers in error messages. * tests/regression.at (Fix user actions without a trailing semicolon): Remove. Covered by new test. (cherry picked from commit e8cd1ad655bcc704b06fb2f191dc3ac1df32b796) --- ChangeLog | 16 ++++++ src/scan-code.l | 64 ++++++++++++++++++------ tests/actions.at | 117 ++++++++++++++++++++++++++++++++++++++++++++ tests/input.at | 34 ++++++------- tests/regression.at | 24 --------- 5 files changed, 198 insertions(+), 57 deletions(-) diff --git a/ChangeLog b/ChangeLog index 2469f912..5104afbf 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,19 @@ +2008-12-07 Di-an Jan + + Implement the FIXME that ends an user action with a semicolon + if it seems necessary. + * src/scan-code.l (flex rules section): Flag cpp directive from + any `#' to the first unescaped end-of-line. Semicolon is not + needed after `;', `{', '}', or cpp directives and is needed after + any other token (whitespaces and comments have no effect). + * tests/actions.at (Fix user actions without a trailing semicolon): + New test. + * tests/input.at (AT_CHECK_UNUSED_VALUES): Add semicolons to + to make user actions complete statements. + Adjust column numbers in error messages. + * tests/regression.at (Fix user actions without a trailing semicolon): + Remove. Covered by new test. + 2009-04-14 Akim Demaille doc: minor fixes. diff --git a/src/scan-code.l b/src/scan-code.l index 13a78c27..c076213b 100644 --- a/src/scan-code.l +++ b/src/scan-code.l @@ -81,6 +81,19 @@ splice (\\[ \f\t\v]*\n)* /* Nesting level of the current code in braces. */ int braces_level = 0; + /* Whether a semicolon is probably needed. + The heuristic is that a semicolon is not needed after `{', `}', `;', + or a C preprocessor directive, and that whitespaces and comments + do not affect this flag. + Note that `{' does not need a semicolon because of `{}'. + A semicolon may be needed before a cpp direcive, but don't bother. */ + bool need_semicolon = false; + + /* Whether in a C preprocessor directive. Don't use a start condition + for this because, at the end of strings and comments, we still need + to know whether we're in a directive. */ + bool in_cpp = false; + /* This scanner is special: it is invoked only once, henceforth is expected to return only once. This initialization is therefore done once per action to translate. */ @@ -135,10 +148,12 @@ splice (\\[ \f\t\v]*\n)* "'" { STRING_GROW; BEGIN SC_CHARACTER; + need_semicolon = true; } "\"" { STRING_GROW; BEGIN SC_STRING; + need_semicolon = true; } "/"{splice}"*" { STRING_GROW; @@ -154,46 +169,63 @@ splice (\\[ \f\t\v]*\n)* { "$"("<"{tag}">")?(-?[0-9]+|"$") { handle_action_dollar (self->rule, yytext, *loc); + need_semicolon = true; } "@"(-?[0-9]+|"$") { handle_action_at (self->rule, yytext, *loc); + need_semicolon = true; } "$" { warn_at (*loc, _("stray `$'")); obstack_sgrow (&obstack_for_string, "$]["); + need_semicolon = true; } "@" { warn_at (*loc, _("stray `@'")); obstack_sgrow (&obstack_for_string, "@@"); + need_semicolon = true; + } + "[" { + obstack_sgrow (&obstack_for_string, "@{"); + need_semicolon = true; + } + "]" { + obstack_sgrow (&obstack_for_string, "@}"); + need_semicolon = true; } - "{" STRING_GROW; ++braces_level; + ";" STRING_GROW; need_semicolon = false; + "{" STRING_GROW; ++braces_level; need_semicolon = false; "}" { bool outer_brace = --braces_level == 0; /* As an undocumented Bison extension, append `;' before the last brace in braced code, so that the user code can omit trailing `;'. But do not append `;' if emulating Yacc, since Yacc does - not append one. Also, some output languages (like Java) do not - accept an extra semicolon, so don't append if the user specified - a skeleton or language. - - FIXME: Bison should warn if a semicolon seems to be necessary - here, and should omit the semicolon if it seems unnecessary - (e.g., after ';', '{', or '}', each followed by comments or - white space). Such a warning shouldn't depend on --yacc; it - should depend on a new --pedantic option, which would cause - Bison to warn if it detects an extension to POSIX. --pedantic - should also diagnose other Bison extensions like %yacc. - Perhaps there should also be a GCC-style --pedantic-errors - option, so that such warnings are diagnosed as errors. */ + not append one. */ if (outer_brace && !yacc_flag && language_prio == default_prio - && skeleton_prio == default_prio) - obstack_1grow (&obstack_for_string, ';'); + && skeleton_prio == default_prio && need_semicolon && ! in_cpp) + { + warn_at (*loc, _("a `;' might be needed at the end of action code")); + warn_at (*loc, _("future versions of Bison will not add the `;'")); + obstack_1grow (&obstack_for_string, ';'); + } STRING_GROW; + need_semicolon = false; } + + /* Preprocessing directives should only be recognized at the beginning + of lines, allowing whitespace including comments, but in C/C++, + `#' can only be the start of preprocessor directives or within + `#define' directives anyway, so don't bother with begin of line. */ + "#" STRING_GROW; in_cpp = true; + + {splice} STRING_GROW; + [\n\r] STRING_GROW; if (in_cpp) in_cpp = need_semicolon = false; + [ \t\f] STRING_GROW; + . STRING_GROW; need_semicolon = true; } diff --git a/tests/actions.at b/tests/actions.at index afbc94db..32bfc34e 100644 --- a/tests/actions.at +++ b/tests/actions.at @@ -1300,3 +1300,120 @@ AT_CLEANUP]) AT_CHECK_ACTION_LOCATIONS([[%initial-action]]) AT_CHECK_ACTION_LOCATIONS([[%destructor]]) AT_CHECK_ACTION_LOCATIONS([[%printer]]) + + +## ----------------------------------------------- ## +## Fix user actions without a trailing semicolon. ## +## ----------------------------------------------- ## + +AT_SETUP([[Fix user actions without a trailing semicolon]]) + +# This feature is undocumented, but we accidentally broke it in 2.3a, +# and there was a complaint at: +# . + +AT_DATA([input.y], +[[%% +start: test2 test1 test0 testc; + +test2 +: 'a' { semi; /* TEST:N:2 */ } +| 'b' { if (0) {no_semi} /* TEST:N:2 */ } +| 'c' { if (0) {semi;} /* TEST:N:2 */ } +| 'd' { semi; no_semi /* TEST:Y:2 */ } +| 'e' { semi(); no_semi() /* TEST:Y:2 */ } +| 'f' { semi[]; no_semi[] /* TEST:Y:2 */ } +| 'g' { semi++; no_semi++ /* TEST:Y:2 */ } +| 'h' { {no_semi} no_semi /* TEST:Y:2 */ } +| 'i' { {semi;} no_semi /* TEST:Y:2 */ } +; +test1 + : 'a' { semi; // TEST:N:1 ; +} | 'b' { if (0) {no_semi} // TEST:N:1 ; +} | 'c' { if (0) {semi;} // TEST:N:1 ; +} | 'd' { semi; no_semi // TEST:Y:1 ; +} | 'e' { semi(); no_semi() // TEST:Y:1 ; +} | 'f' { semi[]; no_semi[] // TEST:Y:1 ; +} | 'g' { semi++; no_semi++ // TEST:Y:1 ; +} | 'h' { {no_semi} no_semi // TEST:Y:1 ; +} | 'i' { {semi;} no_semi // TEST:Y:1 ; +} ; +test0 + : 'a' { semi; // TEST:N:1 {} +} | 'b' { if (0) {no_semi} // TEST:N:1 {} +} | 'c' { if (0) {semi;} // TEST:N:1 {} +} | 'd' { semi; no_semi // TEST:Y:1 {} +} | 'e' { semi(); no_semi() // TEST:Y:1 {} +} | 'f' { semi[]; no_semi[] // TEST:Y:1 {} +} | 'g' { semi++; no_semi++ // TEST:Y:1 {} +} | 'h' { {no_semi} no_semi // TEST:Y:1 {} +} | 'i' { {semi;} no_semi // TEST:Y:1 {} +} ; + +testc +: 'a' { +#define TEST_MACRO_N \ +[]"broken\" $ @ $$ @$ [];\ +string;"} +| 'b' { +no_semi +#define TEST_MACRO_N \ +[]"broken\" $ @ $$ @$ [];\ +string;"} +]]) + +AT_BISON_CHECK([[-o input.c input.y]], [0], [], +[[input.y:8.48: warning: a `;' might be needed at the end of action code +input.y:8.48: warning: future versions of Bison will not add the `;' +input.y:9.48: warning: a `;' might be needed at the end of action code +input.y:9.48: warning: future versions of Bison will not add the `;' +input.y:10.48: warning: a `;' might be needed at the end of action code +input.y:10.48: warning: future versions of Bison will not add the `;' +input.y:11.48: warning: a `;' might be needed at the end of action code +input.y:11.48: warning: future versions of Bison will not add the `;' +input.y:12.48: warning: a `;' might be needed at the end of action code +input.y:12.48: warning: future versions of Bison will not add the `;' +input.y:13.48: warning: a `;' might be needed at the end of action code +input.y:13.48: warning: future versions of Bison will not add the `;' +input.y:20.1: warning: a `;' might be needed at the end of action code +input.y:20.1: warning: future versions of Bison will not add the `;' +input.y:21.1: warning: a `;' might be needed at the end of action code +input.y:21.1: warning: future versions of Bison will not add the `;' +input.y:22.1: warning: a `;' might be needed at the end of action code +input.y:22.1: warning: future versions of Bison will not add the `;' +input.y:23.1: warning: a `;' might be needed at the end of action code +input.y:23.1: warning: future versions of Bison will not add the `;' +input.y:24.1: warning: a `;' might be needed at the end of action code +input.y:24.1: warning: future versions of Bison will not add the `;' +input.y:25.1: warning: a `;' might be needed at the end of action code +input.y:25.1: warning: future versions of Bison will not add the `;' +input.y:31.1: warning: a `;' might be needed at the end of action code +input.y:31.1: warning: future versions of Bison will not add the `;' +input.y:32.1: warning: a `;' might be needed at the end of action code +input.y:32.1: warning: future versions of Bison will not add the `;' +input.y:33.1: warning: a `;' might be needed at the end of action code +input.y:33.1: warning: future versions of Bison will not add the `;' +input.y:34.1: warning: a `;' might be needed at the end of action code +input.y:34.1: warning: future versions of Bison will not add the `;' +input.y:35.1: warning: a `;' might be needed at the end of action code +input.y:35.1: warning: future versions of Bison will not add the `;' +input.y:36.1: warning: a `;' might be needed at the end of action code +input.y:36.1: warning: future versions of Bison will not add the `;' +]]) +AT_CHECK([[grep -c '/\* TEST:N:2 \*/ }$' input.c]], [0], [[3 +]]) +AT_CHECK([[grep -c '/\* TEST:Y:2 \*/ ;}$' input.c]], [0], [[6 +]]) +AT_CHECK([[sed -n '/TEST:N:1/{N +s/\n//gp}' input.c | grep -c '// TEST:N:1 [;{}]*}$']], [0], [[6 +]]) +AT_CHECK([[sed -n '/TEST:Y:1/{N +s/\n//gp}' input.c | grep -c '// TEST:Y:1 [;{}]*;}$']], [0], [[12 +]]) +AT_CHECK([[sed -n '/^#define TEST_MACRO_N/{N +N +s/\n//gp}' input.c | grep -F -xc '#define TEST_MACRO_N \[]"broken\" $ @ $$ @$ [];\string;"}']], + [0], [[2 +]]) + +AT_CLEANUP diff --git a/tests/input.at b/tests/input.at index bb036c38..57f3b641 100644 --- a/tests/input.at +++ b/tests/input.at @@ -97,16 +97,16 @@ m4_ifval($1, [ ], [_AT_UNUSED_VALUES_DECLARATIONS ])[[%% start: - 'a' a { $]2[ } | 'b' b { $]2[ } | 'c' c { $]2[ } | 'd' d { $]2[ } | 'e' e { $]2[ } -| 'f' f { $]2[ } | 'g' g { $]2[ } | 'h' h { $]2[ } | 'i' i { $]2[ } | 'j' j { $]2[ } -| 'k' k { $]2[ } | 'l' l { $]2[ } + 'a' a { $]2[; } | 'b' b { $]2[; } | 'c' c { $]2[; } | 'd' d { $]2[; } +| 'e' e { $]2[; } | 'f' f { $]2[; } | 'g' g { $]2[; } | 'h' h { $]2[; } +| 'i' i { $]2[; } | 'j' j { $]2[; } | 'k' k { $]2[; } | 'l' l { $]2[; } ; a: INT | INT { } INT { } INT { }; b: INT | /* empty */; -c: INT | INT { $]1[ } INT { $2 } INT { $4 }; -d: INT | INT { } INT { $]1[ } INT { $2 }; -e: INT | INT { } INT { } INT { $]1[ }; +c: INT | INT { $]1[; } INT { $2; } INT { $4; }; +d: INT | INT { } INT { $]1[; } INT { $2; }; +e: INT | INT { } INT { } INT { $]1[; }; f: INT | INT { } INT { } INT { $]$[ = $]1[ + $]3[ + $]5[; }; g: INT | INT { $$; } INT { $$; } INT { }; h: INT | INT { $$; } INT { $$ = $2; } INT { }; @@ -123,18 +123,18 @@ input.y:11.10-32: warning: unused value: $]1[ input.y:11.10-32: warning: unused value: $]3[ input.y:11.10-32: warning: unused value: $]5[ input.y:12.9: warning: empty rule for typed nonterminal, and no action -]]m4_ifval($2, [[[input.y:13.14-19: warning: unset value: $$ -input.y:13.25-39: warning: unset value: $$ -]]])[[input.y:13.10-59: warning: unset value: $]$[ -input.y:13.10-59: warning: unused value: $]3[ -input.y:13.10-59: warning: unused value: $]5[ +]]m4_ifval($2, [[[input.y:13.14-20: warning: unset value: $$ +input.y:13.26-41: warning: unset value: $$ +]]])[[input.y:13.10-62: warning: unset value: $]$[ +input.y:13.10-62: warning: unused value: $]3[ +input.y:13.10-62: warning: unused value: $]5[ ]]m4_ifval($2, [[[input.y:14.14-16: warning: unset value: $$ -]]])[[input.y:14.10-47: warning: unset value: $]$[ -input.y:14.10-47: warning: unused value: $]3[ -input.y:14.10-47: warning: unused value: $]5[ -input.y:15.10-36: warning: unset value: $]$[ -input.y:15.10-36: warning: unused value: $]3[ -input.y:15.10-36: warning: unused value: $]5[ +]]])[[input.y:14.10-49: warning: unset value: $]$[ +input.y:14.10-49: warning: unused value: $]3[ +input.y:14.10-49: warning: unused value: $]5[ +input.y:15.10-37: warning: unset value: $]$[ +input.y:15.10-37: warning: unused value: $]3[ +input.y:15.10-37: warning: unused value: $]5[ input.y:17.10-58: warning: unset value: $]$[ input.y:17.10-58: warning: unused value: $]1[ ]]m4_ifval($2, [[[input.y:17.10-58: warning: unused value: $]2[ diff --git a/tests/regression.at b/tests/regression.at index fa2278a8..32e676c6 100644 --- a/tests/regression.at +++ b/tests/regression.at @@ -1247,27 +1247,3 @@ AT_COMPILE([[input]]) AT_PARSER_CHECK([[./input]]) AT_CLEANUP - - - -## ----------------------------------------------- ## -## Fix user actions without a trailing semicolon. ## -## ----------------------------------------------- ## - -AT_SETUP([[Fix user actions without a trailing semicolon]]) - -# This feature is undocumented, but we accidentally broke it in 2.3a, and there -# was a complaint at: -# . - -AT_DATA([input.y], -[[%% -start: {asdffdsa} ; -]]) - -AT_BISON_CHECK([[-o input.c input.y]]) -AT_CHECK([[sed -n '/asdffdsa/s/^ *//p' input.c]], [[0]], -[[{asdffdsa;} -]]) - -AT_CLEANUP -- 2.45.2